Bearings for bodies of revolution

ABSTRACT

A body of revolution mounted for rotation about a non-rotary bearing which comprises a segment received by a bore of the body and articulated about a single pivot axis, normal to the bore axis, on a support shaft, the segment in use of the body being positioned in the line of and on that side of the shaft directed toward a radial load to be applied to the body.

FIG. 1 further illustrates a spring supporting assem bly 30 which may be hooked on to the frame in the manner illustrated in FIG. 1.

The short legs 26 and the long legs 28 are used only at the corners of the frame 20 (or 22). Where an upper portion of the article, forming an arm or back thereof, is to be supported between the corners of the lower frame 20, the manufacturer selects from different support stubs such as the support stub 32 shown in FIG. 1. Thus, this support stub 32 is fixed at its lower end, as by welding or bolts or the like, to the frame 20 extending upwardly therefrom in the manner illustrated in FIG. 1 for the purpose of supporting an upper portion of the article of furniture at a location between the corners where the legs 26 or 28 are located.

FIG. 1 further illustrates an upper frame 34 which may be made of tubular metallic stock of a diameter slightly smaller than that of the stock from which the legs 26 and 28 are formed, so that the lower extensions 36 of the upper frame 34 may be telescopically received in the upper ends of a pair of legs 28, as is apparent from FIG. 1. The upper frame 34 is reinforced by an elongated rod 38 of relatively small diameter which is fixed at its opposed ends in any suitable way to the pair of side arms of the upper frame 34 so as to reinforce the latter. It will be noted that while the upper frame 34 extends in a generally upright direction upwardly from the legs 28 it is at the same time inclined so as to extend outwardly beyond the outer frame 20, for a purpose referred to below.

The frame 34 is but one example of a plurality of different frames of different configurations and sizes which are kept on hand by the manufacturer so that by a selection from among the different frames it is possible to manufacture articles of furniture of different configurations as will be apparent from the description which follows.

Thus, FIG. 2 shows an upper frame 40 which is of a horizontal rectangular configuration. and which has fixed thereto lower extensions 42 adapted to be fixed in any suitable way to longer legs 28 or intermediate support stubs 32 in the manner described in greater detail below, the frame 40 forming part of an arm of the article of furniture which is of a relatively wide low configuration.

FIG. 3 is a perspective illustration of an upper frame 44 which is identical with the frame 34 except that it is shorter. Thus the left lower extension 46 of the frame 44 may be joined to the left leg 28 of FIG. I while the right lower extension 46 may be joined tothe support stub32. In this case also the tubular stock which forms the frame 44 may be telescopically received in the upper open ends of the left leg 28 and support stub 32 of FIG. 1, and it will be noted that frame 44 is also reinforced by an elongated rod 48.

FIG. 4 illustrates a table arm 50 according to the invention. This table arm includes a relatively rigid wall 52 made of wood, metal, plastic, or the like, and having a suitably finished upper surface 54. At its lower surface the plate 52 is fixed in any suitable way as by glue, screws, or the like, to a pair of smaller square plates 56 which in turn are fixed with lower extensions 58 made of the same tubular stock as the tubular stock used for any of the upper frames referred to above so that these lower extensions 58 may be received, for example, in the left leg 28 and the supportstub 32 of FIG. 1.

Finally, FIG. 6 illustrates a further embodiment of an upper frame 60 according to the invention. This upper frame 60 is made of the same tubular stock as any of the upper frames referred to above, but in this case the upper frame 60 is not inclined as is the case with the frames 34 and 44. Instead the entire frame is located in a single vertical plane, although its opposed side arms are inclined inwardly toward each other. These arms terminate in the lower extensions 62 which are adapted to be telescopically received in supports such as the left leg 28 of FIG. 1 and the support stub 32. It will be noted that in this case also the upper frame 60 is reinforced by an elongated rod 64.

In addition to the components described above, the present invention comtemplates the use of legs and support stubs which are offset outwardly beyond the lower frame for a purpose referred to below. Thus, FIG. 5 fragmentarily illustrates part of the frame 20 of FIG. 1 which in the case of FIG. 5 forms an article of furniture which may be identical with that of FIG. 1 except that the left leg 28 of FIG. 1 is replaced by a leg 66 and the support stub 32 of FIG. 1 is replaced by a support stub 68. The relatively long leg 66 of FIG. 5 has upwardly beyond the frame 20 an outwardly inclined portion 70 which terminates in an upper end 72 adapted to receive the left lower extension 62 of the frame 60 of FIG. 6. The support stub 68 has an outwardly inclined portion 74 fixed to and extending upwardly and outwardly from the frame 20 and terminating in a vertical portion which is adapted to telescopically receive the right lower extension 62 of the frame 60 of FIG. 6. Thus, in this case, as will be apparent from the description below, these outwardly offset legs and support stubs are adapted to be used with a vertical frame of the type shown in FIG. 6 which is to form part of a relatively thin arm of the article of furniture.

It is possible by combining the component described above and shown in FIGS. 1-6 in different ways to achieve an almost limitless varieth in the configurations of the articles of furniture. For this purpose a lower frame such as the frame 20 of FIG. 1 with preselected legs and support stubs fixed thereto is embedded in a block of resilient foam plastic. Although manydifferent plastics are available for this purpose, it is preferred to use a urethane foam which is wrapped in a relatively puffy coat of Dacron. The urethane foam is reinforced by the frame and leg structure as well as the spring assembly 30, and preferably the urethane foam is selfskinned. In other words the cells may be closed at the outer surface of the block of urethane foam. The surrounding coat of Dacron lends an additional softness to the structure.

Thus, referring to FIG. 8, there is shown therein the lower frame and leg assembly of FIG. 1 in a side elevation with the resilient plastic block in which the components are embedded being illustrated in a dot-dash line illustration. Thus, FIG. 8 shows in phantom lines a lower block 76 in which the lower frame 20 and the legs and support stub fixed thereto are embedded. For this purpose the lower frame 20 and the legs and support stub fixed thereto are placed in a mold in which the foam plastic is molded. It will be: noted that the legs extend downwardly beyond the block 76 into engagement with the floor 78, and the bottoms of the legs may be closed with any suitable closure elements which engage the floor 78 in a predetermined manner. The block of foam plastic surrounded with Dacron extends 1 BEARINGS FOR BODIES OF REVOLUTION The present invention is concerned with bearings for bodies of revolution.

When bodies of revolution such as pulleys, idlers, friction wheels, or toothed wheels are in contact with an element which exerts a radial force on them, they can undergo abnormal contact stresses on their periphery due to pressures which are badly distributed along the contact generatrices. This phenomen results, for example, for deformations or from incorrect positioning of the contacting elements.

It is an object of this invention to provide an improved bearing for a body of revolution.

According to the present invention there is provided a rotary body of revolution mounted on a non-rotary bearing, which comprises a segment received by a bore of the body for location on the side of the point of application of a radial load to be exerted on the body of revolution, and a segment supporting fixed shaft received by the body of revolution, the segment being ar-- ticulated relative to the shaft with a single degree of freedom whose pivot axis is perpendicular to the axis of the bore of the bearing and to the direction of the radial load.

The arrangement may be applied to any body of revolution rotating about a fixed bearing and undergoing a unidirectional radial load and may incorporate plain or ball-bearing mountings.

In an application of particular interest, this arrangement may be used for support idlers on which a heavy rotary body, such as a crusher or rotary furnace, rests and rotates. The rolling pressure stresses undergone by the peripheral rolling path integral with the rotary body are then smaller than those which would be undergone by a rolling path in contact with idlers mounted on fixed shafts. The requirements for rigidity of the structure subjected to risks of deformation or of rupture of the envelope of the rotary body are then less draconian.

The invention is described below with more details, referring to embodiments given as examples and shown on the drawing.

FIG. 1 shows the device according to the invention, in section along a plane passing through the axis of the journal, and in which the guiding of the body of revolution on the journal is obtained by sliding.

FIG. 2 shows the mechanism along a section bb of FIG. 1.

FIG. 3 is a detailed view of FIG. 1, showing in particular the arrangements for sealing and for the cooling of the lubricant.

FIG. 4 shows the articulated segment of the journal.

FIG. 5 shows an application in which a body of revolution according to the invention is in contact with a heavy rotary body.

FIG. 6 represents a variation of the mechanism, in section along the axis of the journal, in which guiding is effected by rolling.

The mechanism comprises, referring at first to FIGS. 1 and 2, an articulated journal formed essentially by a fixed, non-rotating shaft 1, and a segment 2, articulated relative to each other by a ball with one degree of freedom, the fixed shaft 1 :being supported by two pedestal bodies 3. The articulation between the segment and the shaft is ensured by contact of a convex hemi-cylindrical surface 41 of segment 2 with a concave hemicylindrical surface 51 of the shaft 1. More precisely, the external surface 41 of a transverse key 4 with a hemi-cylindrical back fixed to segment 2 rests on a hemi-cylindrical cup 5 fast with the shaft 1, the key 4 being fiirthermore guided according to the axis of the articulation and relative to the cup 5 by means of axial stops 6. The hemi-cylindrical surface 41 of the key 4 is not an exact fit in its mounting 51 of the cup 5, in order that the key 4 rolls without sliding on the cup 5 during oscillations of segment 2, the play being determined such that the contact stresses remain acceptable. The key 4 and the cup 5 can be made of a hard, wearresistant material, for example hard tempered steel. Rotary guiding of the rotary body of revolution 7is effected by the segment 2, situated, relative to the articulation, on the side of the body exerting the radial load labelled f on FIG. 2. The rotary body of revolution 7 is supported and guided in rotation by sliding of its bore on the segment 2, a lining 8 being; interposed. The lining 8 is, as shown on FIG. 4, fixed to the segment 2 by screws 9, a stop 10 resisting the tangential forces pro duced by the rotation of the body of revolution 7 according to the arrow 11. The body of revolution 7 is laterally guided by sliding of two stop studs 14 fast with the lateral faces of the segment against two thrust collars 12 made fast with body 7 by means of collars 13 set in the said body. Lubrication grooves 27 are formed in the stop studs 14.

Lubrication is ensured by the total or partial filling with oil 20 of the volume comprised between the journal l and the bore of the body 7. To prevent exit of oil, flat seals 15 mounted in cylindrical rings 16 which are immobilised from rotation, ensure by means of springs 18 a permanent contact with the thrust collars l2 integral with body 7; sealing between the rings 16 and the journal 1 is effected by a toroidal joint which permits the ring 16 to follow the oscillations of the body 7. Leakages of oil are collected by lateral housings 17. To protect against external pollution, the housings 17 comprise a fiat seal 19 which rubs on the collar 12. Leakages of oil are then collected by gravity in a reservoir 22. Artificial cooling of the lubricant is ensured, for mechanisms subjected to strong heating by a cooling device 21 formed by finned tubes immersed in the oil 20.

The removal of used oilcan be effected by a drain hole 71;

At the moment of starting, and possibly during the periods of rotation at a very low speed, sliding between the lining 8and the body 7 develops considerable friction. This'disadvantage is avoided by temporarily in' jecting oil between the two surfaces. Referring to FIGS. 4 and5, the device ensuring this injection of oil comprises a high pressure pump 26 which, via channels 23, 24, distributesthe oil contained in reservoir22'to the oil exit nozzles 25, opening at the level of the zone of friction, the leakages of oil leaving the flat joints 15 being returned to the reservoir. 24 by the channels 28 and 29. The pedestal bodies 3 supporting the support shaft 1 permit an adjustment in height and transverse adjustment. For this purpose, the shaft l can be displaced parallel to the axis of the ball joint on a slide 31, the position chosen being determined by the adjustment of screws 30 locked by lock nuts. Oil under pressure, supplied via channel 32 and injected beneath the shaft 1 in the zone of sliding on the slide 31, can permit this adjustment under load.

In the variation of FIG. 6, guiding in rotation of the rotary body 7 is obtained by bearings 33, whose external rings are pressed between the collars l2 and a spacer bush 34 centred on the body 7, and the internal rings of which bear on a shoulder of segment 2.

It is to be understood that the invention is not limited by the embodiments which have been described, and these can be modified without departing from the scope of the invention.

Thus the articulation effected between two separate pieces may also be effected by two concave cups such as 5, one being locked in the segment 2, the other in the shaft 1, and forming the mounting for a cylindrical shaft. The sealing means effected in the variants by the flat seals can also be effected by other means such as lipped joints.

In the variation in which the body of revolution is guided on the journal by sliding, the anti-friction lining can equally be disposed all around the bore of the rotary body.

I claim:

1. A bearing construction comprising a rotary body of revolution, a non-rotary bearing supporting said body, an axis for said bearing, a segment articulated perpendicularly to said axis on said bearing, said segment being located adjacent to point of application of forces exerted on said bearing, said rotary body being mounted on said segment, bearings between said segment and said rotary body, a key, a hemi-cylindrical convex surface for said key, said key extending perpendicularly to the axis of said rotary body and mounted in said segment, a cup mounted in said bearing, a hemicylindrical concave surface in said cup receiving said key and providing said articulation between said segment and said bearing and stops preventing axial movement of said segment on said key and of said key and of said cup on said bearing.

2. A bearing construction according to claim 1, the radius of said concave hemi-cylindrical surface being greater than the radius of said convex hemi-cylindrical surface.

3. A bearing construction as described in claim 1, including annular spaces between the cylindrical bore of said body of revolution and said bearing, non-rotary sealing means closing said spaces axially at the ends of said segment, said sealing means being movable axially relative to said fixed bearing, and means biasing said sealing means against said body of revolution. 

1. A bearing construction comprising a rotary body of revolution, a non-rotary bearing supporting said body, an axis for said bearing, a segment articulated perpendicularly to said axis on said bearing, said segment being located adjacent to point of application of forces exerted on said bearing, said rotary body being mounted on said segment, bearings between said segment and said rotary body, a key, a hemi-cylindrical convex surface for said key, said key extending perpendicularly to the axis of said rotary body and mounted in said segment, a cup mounted in said bearing, a hemi-cylindrical concave surface in said cup receiving said key and providing said articulation between said segment and said bearing and stops preventing axial movement of said segment on said key and of said key and of said cup on said bearing.
 2. A bearing construction according to claim 1, the radius of said concave hemi-cylindrical surface being greater than the radius of said convex hemi-cylindrical surface.
 3. A bearing construction as described in claim 1, including annular spaces between the cylindrical bore of said body of revolution and said bearing, non-rotary sealing means closing said spaces axially at the ends of said segment, said sealing means being movable axially relative to said fixed bearing, and means biasing said sealing means against said body of revolution. 